JP2014527794A - Self-stabilizing solar tracking device - Google Patents

Abstract

A frame for mounting a plurality of solar light tracking units is provided. The frame includes a plurality of leg assemblies, and the leg assemblies are connected to each other by a plurality of trusses, so that the frame does not rely on an external ballast such as a concrete block, and stable and stable by the weight of the frame itself. A structure is obtained. Each of the leg assemblies is provided on a shaft having an attachment end to which a solar tracking unit is attached. Each solar tracking unit includes an armature assembly and at least one motor that controls the orientation and position of the solar panel attached thereto. Each of the solar tracking assemblies includes a frame and a plurality of solar tracking units, and can be assembled in an array using a connector that separates the solar tracking assemblies. Therefore, higher stability can be obtained. Each of the solar tracking assemblies may be provided with a local control unit that controls an individual solar tracking unit. A wide area control unit may be used for controlling the local control unit.

Description

<Reference to prior application>
This application claims priority from US Patent Application No. 61/523817 filed August 15, 2011 and US Patent Application No. 61 / 532,083 filed September 7, 2011. The entire contents of these US patent applications are hereby incorporated by reference.

<Technical field>
The present invention relates to the field of solar energy, and more particularly to tracking solar panel assemblies and their arrangement.

  Solar energy is typically captured by an assembly of photovoltaic (PV) cells that are placed and interconnected on one or more solar panels with a large surface area for the purpose of supplying power. Many solar panels may be arranged in an array.

  In addition to the problems inherent in the development of efficient solar panels that can deliver optimal performance, including manufacturing mismatches and assembly errors, the status of the solar panel installation site is also cost-effective. This is an obstacle to realizing high solar energy collection. Conventionally, a solar tracking system equipped with a tracking controller that adjusts the position of the solar panel can be installed on a flat surface to enable accurate installation of the system, and can be fixed to a sturdy base (for example, , The stability due to concrete driving) was ensured. However, these conditions require additional equipment and manpower, increasing the cost required to install the system in the field.

  The drawings illustrating the preferred embodiments described herein are as follows:

  FIG. 1 is a perspective view showing an assembly of a tracking solar panel installed on the ground.

  FIG. 2 is a partially exploded perspective view showing an installation state of the box-shaped frame portion of the assembly shown in FIG.

  FIG. 3 is a perspective view showing a folded state of the box-type frame portion shown in FIG.

  FIG. 4 is a perspective view showing a leg assembly for attaching to the truss of the box-type frame part shown in FIG.

  5 to 7 are perspective views showing other frame configurations.

  FIG. 8 is a perspective view showing an armature assembly used with the assembly shown in FIG.

  9 and 10 are side views illustrating a solar panel used with the assembly shown in FIG.

  11 and 12 are perspective views showing the photovoltaic modules installed in the assembly shown in FIG.

  FIG. 13 is an explanatory diagram illustrating an example of a plurality of mutually connected frames.

  FIG. 14 is a diagram showing the electrical interconnection and communication interconnection of the plurality of tracking solar panel assemblies shown in FIG.

  FIG. 15 is a flowchart showing an automatic calibration process.

  FIG. 16 is a diagram showing an electrical interconnection and a communication interconnection of a plurality of tracking solar panel assemblies installed in a solar farm.

  By providing a self-stabilizing solar tracking assembly for use with concentrating or non-concentrating solar panels, the stability and alignment of the solar panels can be achieved without the need for ground maintenance. Maintained. A modular and foldable truss structure is provided as a frame that supports a plurality of solar tracking units to which a solar panel can be attached. Each of the solar panels is attached to the solar light tracking unit at the center of gravity or near the center of gravity, and is arranged at the corner or joint of the frame. These structures are intended to reduce or eliminate the need for ballasts (such as concrete blocks) by obtaining higher stability and to facilitate electrical connection and data communication. It can be physically connected to each other in the field. The arrangement of these interconnected structures on a solar farm or sub-farm is provided to efficiently install the structure supporting the solar tracking unit on the ground.

  In FIG. 1, a perspective view of a solar tracking assembly or unit 100 is shown. The assembly 100 typically comprises a ground-mounted frame 10 that supports one or more photovoltaic (PV) tracking modules 200 (also referred to as solar tracking units). In the embodiment shown in FIG. 1, the solar light tracking unit 200 is shown in a state of supporting the solar panel 205. The frame 10 has a plurality of trusses 12 and 22. In the embodiment of FIG. 1, the frame 10 has a first pair of trusses 12, 12 having substantially the same length defining the first opposite side of the frame 10, and the first pair is the remaining pair. A leg assembly is connected to a second pair of trusses 22, 22 having substantially the same length defining opposite sides. Thus, the truss assembly forms a parallelogram frame 10 as a whole, and in this example forms a box or rectangular frame 10. The sides of the frame 10 do not have to be specifically formed of trusses, but will be understood by those skilled in the art as the structural stability benefits that the truss structure provides.

  As shown in FIG. 2, each truss 12 has an upper cord member 14 and a lower cord member 16, and each truss 22 has an upper cord member 24 and a lower cord member 26. The code member 14 and the code member 16 are connected by a set of truss members 17, and the code member 24 and the code member 26 are connected by a set of truss members 27. In this embodiment, each truss 12 includes a set of four truss members 17, and each truss 22 includes a set of four truss members 27. The selection and arrangement of the truss members 17, 27 need not be limited to the embodiment shown. That is, a greater or lesser number of truss members 17, 27 may be used depending on the dimensions and materials selected for the frame 10. In addition, one or more struts 18 are attached between the upper cord member 14 and the lower cord member 16 or one or more struts between the upper cord member 24 and the lower cord member 26. By attaching 28, these cord members may be additionally supported in the vertical direction. In the embodiment of FIG. 2, several struts 18, 28 are provided near the ends of the trusses 12, 22, ie near the junction between adjacent trusses. The number of struts (which may be zero or larger) and placement, as well as the number and placement of truss members, the specific requirements for installation of the solar tracking assembly 100, as well as the frame 10 and tracking module 200. Can be selected according to the unique characteristics of the. These characteristics include the weight of the tracking module 200 to be supported, the material used to manufacture the trusses 12 and 22, and the shape of the trusses 12 and 22.

  As shown in more detail in FIGS. 3 and 4, truss 12 and truss 22 are connected to leg assembly 30 at or near their respective ends. As shown in the example leg assembly illustrated in FIG. 2, each leg assembly 30 includes a shaft 31, and each leg assembly 30 further includes an adjustable foot member 37. Also good. The foot member 37 in the present embodiment includes a plate member 39 that is removable and extends from the stem 38. Stem 38 is attached to shaft 31 of leg assembly 30. In some embodiments, the overall height of the leg assembly 30 can be adjusted, thereby adjusting the overall height of the solar tracking unit 200 when installed, so that the stem 38 to the shaft 31 can be adjusted. The mounting position may be changed. The stem 38 and the plate member 39 may have a configuration different from the configuration described in this specification. In some embodiments, spike members or other mounting components (not shown) in addition to or instead of the plate member 39 may be used to secure the leg assembly to the ground and / or to electrically attach the frame 10. It may be provided for grounding. The tip of the leg assembly 30 serves as an attachment end 35 for attaching an armature assembly that supports the solar light tracking module 200.

  The truss 12, 22 and leg assembly 30, and their respective components, may be manufactured from suitable materials. For example, trusses and leg assemblies may be manufactured from galvanized steel or aluminum, and manufactured from metal tubes that are either open or seamed and formed by extrusion or stretching. May be. Further, in some embodiments, at least the upper cord members 14, 24 may be provided with axial bore holes, or inner grooves that extend from end to end of the cord member and open at both ends. May be formed (not shown). The bore hole and the inner groove are conveniently provided when the cord member is manufactured by tubing. Cables, wires, and hoses, such as air and water hoses, as well as electrical cables and the like, may be passed through the upper cord members 14, 24 and / or the lower cord members 16, 26. Similarly, the leg assembly 30 may be provided with similar bore holes and inner grooves. In the embodiment described herein, leg assembly 30 is a tubular member.

  FIG. 3 shows the three trusses 22, 12, 12 of the frame 10 connected to the leg assembly 30 shown in FIG. In this embodiment, the three trusses are assembled together with the leg assembly 30 in a folded state suitable for transportation. In this configuration, the truss remains connected but is easier to transport than when the frame 10 is fully assembled. The remaining fourth truss 22 may be supplied separately. However, of course, even if the fourth truss is connected in the frame 10, the frame 10 can be folded into a substantially flat structure suitable for transportation. This figure shows flange units 32, 33, 34 provided on the leg assembly 30, which are provided for mounting the trusses 12, 22. The fastening means shown in FIG. 4 used to connect the truss 12, 22 to the leg assembly 30 is convenient for providing a hinge connection between each of the truss 12, 22 and the leg assembly 30. It can be seen from the folded state that it is adopted and thus allows the frame 10 to be transported in a partially assembled state. Further, the trusses 12 and 22 can pass cables, wires, and hoses through the upper cord members 14 and 24 or the lower cord members 16 and 26, respectively. For this reason, these components may be previously passed through the cord member before shipment. This not only reduces the assembly time at the site, but also protects the wiring and the like from the components and reduces the need for expensive connectors.

  In FIG. 4, a further view of the leg assembly 30 is shown. A first lower flange unit 32 is provided near the first end of the leg assembly (ie, near the end connected to the foot member 37). In this embodiment, the flange unit 32 includes a set of four flanges 32a, 32b, 32c and 32d extending from the leg assembly. In the box-shaped frame 10 of the present embodiment, the flanges 32a, 32b, 32c, 32d extend radially and are arranged at substantially equal intervals around the leg assembly 30, that is, at right angles to each other. In the present embodiment, each of the flanges 32a, 32b, 32c, 32d and the lower cord members 16, 26 are provided with corresponding bore holes for receiving the fasteners 42. The lower cord members 16 and 26 are installed in the corresponding flanges 32c and 32d so that the bore holes provided in the respective components are arranged in a substantially line. And the cord member and the flange corresponding to it are connected using the fastener 42. The fastener 42 is also a connection for electrical grounding and facilitates electrical connection between the cord member and the leg assembly 30 via a corresponding flange. The fastener 42 is selected to be suitable for coupling and / or electrically connecting the cord member and the flange, such as a bolt and washer having a thread as shown. The fastener described herein may be, for example, a self-tapping screw or a split pin. In this case, it is not necessary to provide a thread in the bore hole provided in the flange unit 32 and the trusses 12 and 22.

  Of course, other means of attaching the trusses 12, 22 to the leg assembly 30 may be used. For example, the leg assembly 30 may not be provided with flange units 32, 33, 34; instead, the upper cord members 14, 24 and the lower cord members 16, 26 are attached directly to the shaft. May be. Even in this case, the flanges 32b and 32c respectively support the lower cord members 26 and 16 belonging to the trusses 22 and 12 attached in contact therewith. As shown in FIG. 4, the flange units 32, 33, 34 are fixed in place on the shaft 31 of the leg assembly 30, but in some embodiments, the flange units 32, 33, 34 may be mounted at different height positions on the shaft 31. The flange unit 32 may include, for example, a tubular main body and flanges 32a, 32b, 32c, and 32d extending therefrom. Here, the tubular main body has an internal dimension larger than the external dimension of the shaft 31. When the shaft 31 and the tubular body of the flange unit 32 are circular, the flange unit 32 can be rotated so as to have a desired arrangement. The flange unit 32 may be slid along the length of the shaft 31 and then fixed in place with an appropriate fastener. However, in order to simplify the introduction of the system in the field, the flange unit is fixed in place.

  Once the frame 10 is assembled, the two flanges 32a, 32d in this embodiment are not used for connection to the truss 12 or 22. However, it will be appreciated that the provision of additional flanges 32a, 32d couples the leg assembly 30 to an additional truss (not shown) and to a spacing arm described below with reference to FIG. It becomes possible.

  The upper flange units 33 and 34 may be configured in the same form as the lower flange unit 32 described above. The upper flange units 33, 34 are separated from the lower flange unit 32 along the shaft 31, so that the upper cord members of the trusses 12, 22 also have the same configuration as the lower flange unit 32. 14 and 24. In the present embodiment, the upper cord members 14 and 24 are disposed between the first flange unit 33 and the second flange unit 34. Here, the first flange unit 33 supports the cord member. Thereafter, the cord members 14 and 24 are firmly fixed between the two flange units by using the fasteners 44.

  One or more leg assemblies 30 may have one or more ports 40. The port 40 is located at or near the height of the upper cord members 14, 24 when the upper cord member 24 is attached to the leg assembly. One such port 40 is shown in FIG. Cables, wires, and hoses threaded through the cord members 14, 24 extend into the first port 40 corresponding to the open end of the first upper cord member 14 and through the leg assembly 30, the second Can exit from the second port corresponding to the open end of the upper cord member 24. The cable, wire, and hose continue through the second upper cord member 24. Alternatively, some cables and wires may be threaded through the cord members 14, 24 while other cables and wires may be attached to the exterior of the cord members 14, 24. For example, when the cord member 24 is electrically grounded, the low voltage control cable is passed through the cord members 14 and 24 and the high voltage power control is performed in order to electrically insulate the low voltage control cable from the high voltage power control cable. The cable can extend along the outside of the cord members 14,24. In other examples, some cables and wires are attached to one side of the cord members 14, 24 while other cables and wires are cords so that the cord members 14, 24 function as electrical insulators. It may be attached to the other side surface of the members 14 and 24. In yet another example, cables and wires may be routed through the leg assembly 30 and into the ground where they can be electrically isolated. The leg assembly 30 may further include a separator that insulates the high and low voltage cables within the leg assembly 30.

  The exemplary frame 10 that is box-shaped provides a sufficiently stable configuration for mounting the solar tracking unit 200. However, those skilled in the art will appreciate that other configurations are possible. An example of a triangular frame 50 is shown in FIG. 5 with three trusses 52 attached to the leg assembly 54. In this particular form, each truss 52 is substantially the same length, thus forming a substantially equilateral triangular form. However, the truss 52 may have two or three different lengths. Truss 52 and leg assembly 54 may be coupled in the same manner as described with respect to FIG. However, unlike the embodiment of FIG. 4, the flanges extending from the leg assembly 54 are positioned at an angle suitable for connecting the trusses into the desired triangular configuration.

  Two other possible configurations are shown in FIGS. FIG. 6 is a schematic view of a frame 60 having an X-shaped configuration, with four trusses 62 attached to a central post 66 at a central point, and four leg assemblies 64 at each tip of the truss 62. It is connected. Although not shown, the solar tracking unit is attached to at least one of the leg assemblies 64. Therefore, the arrangement of the sunlight tracking unit is the same as the arrangement of the sunlight tracking unit 200 attached to the box-shaped frame 10 of FIG. FIG. 7 shows a further X-shaped configuration. Here, the truss 72 is again attached to the central column 76 and extends in an arrangement similar to that shown in FIG. On the other hand, a tip post 74 is attached to the tip of each truss 72, and two leg assemblies 78 are connected to each tip post 74 using a support beam 77 or a further truss. Similar to the embodiment of FIG. 6, the frame 70 can support at least four solar tracking units (not shown), which are attached to the tip post 74. The embodiment shown in FIGS. 6 and 7 is foldable to facilitate transport. The central struts 66, 76 are provided with hinge connections so that the trusses 62, 72 are rotatable. The tip post 74 of FIG. 7 is also provided with a hinge so that the leg assembly 78 can be folded.

  In the embodiment shown in FIG. 1, the solar tracking unit 200 is attached to the attachment end 35 of the leg assembly 30. The solar tracking unit 200 has the armature assembly 80 shown in FIG. Each armature assembly 80 may be fitted with a solar panel, such as a solar panel described in more detail below with reference to FIGS. Each solar light tracking unit 200 may be provided with a solar position sensor (not shown). Solar position sensors are used for computer calibration to ensure that sunlight is normally incident on the surface of the solar panel, and for unpredictable situations and other events that occur during the introduction of the system to the field. To compensate for problems. Here, the unpredictable situation is, for example, uneven terrain that affects the inclination angle of the solar light tracking unit 200. Other problems include, for example, manufacturing errors that occur when manufacturing the solar panels 210, 220 and their components, and differences between the actual sun position and the predicted sun position.

  The armature assembly 80 has a shaft 82 having an outer diameter that fits within the mounting end 35 of the leg assembly 30. The orientation of the shaft 82 within the leg assembly 30 may be determined upon introduction of the system into the field, but usually the orientation depends on the desired state in which the frame 10 and the solar tracking unit 200 are aligned north-south. Determined. Adjustment of the solar light tracking unit 200 on the frame 10 is performed by one or more notches or morning glory openings 93 provided at the first end 82 ′ of the shaft 82. Here, the notch or morning glory 93 receives a corresponding one or more protrusions or pins (not shown) in the mounting end 35 of the leg assembly 30. In the embodiment of FIG. 8, a first collar 98 and a second collar 99 are provided on the shaft 82 away from the first end 82 '. Each of the first collar portion 98 and the second collar portion 99 has a larger outer diameter than the shaft 82 or the first end 82 ′. Here, the first collar 98 is sized to fit within the mounting end 35 of the leg assembly 30 (not shown in FIG. 8) with minimal clearance or no clearance. The second collar portion 99 is substantially the same as the first collar portion 98 so that the second collar portion 99 fits in the attachment end 35 in the same manner as the first collar portion 98 with the lip 81 having a larger diameter provided above. It may have an outer diameter. When the leg assembly 30 is attached, the lip 81 is placed on the upper edge of the attachment end 35. Thus, the position of the lip 81 on the shaft 82 and, in some embodiments, the depth of the notch 93 determines the height of the armature assembly 80 attached to the leg assembly 30. In other embodiments, the entire second collar 99 may have an outer diameter that is at least greater than the inner diameter of the mounting end 35 of the leg assembly 30, while the lip 81 may be removed. In this case, the second collar portion 99 is placed on the upper end edge of the attachment end 35. When the shaft 82 is attached, the holes 94 and other receiving holes (for example, bores and other openings) are aligned to receive a fastener (not shown, for example, a positioning screw) provided on the mounting end 35. The shaft 82 can be more firmly fixed to the mounting end 35. In some embodiments, a bore hole 36 (shown in FIG. 4) is provided in the mounting end 35 for receiving a fastener.

  The armature assembly includes a yoke 84 provided on the yoke mounting portion 79, a cross piece 85 extending from the yoke mounting portion 79, and first and second arms 86 extending from the cross piece 85. In the form shown in FIG. 8, these arms 86 extend substantially perpendicularly from the cross piece 85 and are substantially parallel to the yoke mounting portion 79. The arms 86 are substantially parallel to each other. However, in other embodiments, the position of the arm with respect to the cross piece 85 and the yoke attachment portion 79 may be changed according to the configuration of the solar panel attached to the armature assembly 80. A gusset 83 for adding rigidity is attached to the cross piece 85 and the arm 86. The yoke mounting portion 79 is fixed to the center of the cross piece 85 in a penetrating state. The yoke attachment 79, the cross piece 85, the arm 86, and the gusset 83 may be manufactured as individual parts that are welded together to form the yoke 84. Alternatively, the yoke 84 may be integrally formed as one part by a die casting method.

  Although not shown in FIG. 8, bearings and bushings may be provided in the yoke mounting portion 79, thereby facilitating rotation of the yoke 84 around the shaft 82. The first drive system for controlling the yawing of the solar light tracking unit 200 includes a first gear 90. The first gear 90 is fixed to the shaft 82 and is therefore fixed to the frame 10. In addition, a second gear 91 that meshes with the first gear 90 is provided on the cross piece 85, and the second gear 91 is the surface of the same cross piece 85 as that on which the first gear 90 is provided. It extends from. The second gear 91 is disposed with respect to the yoke 84. In the embodiment of FIG. 8, the first and second gears 90 and 91 are arranged inside the yoke 84, that is, between the arms 86. A first drive assembly including a motor and gear box 92 is provided for the second gear 91. The first drive assembly rotates the yoke 84 about the fixed first gear 90 and shaft 82 by controlling the rotation of the second gear 91. As an example, a suitable drive assembly has a weathering and durability stepper motor. This stepping motor has an output shaft, and the output shaft is connected to a closed gear box having an output shaft with a pinion gear (second gear 91). Therefore, the pinion gear (second gear 91) can supply higher torque than the stepping motor, and the increase in torque depends on the gear ratio of the gear included in the hermetic gear box. The pinion gear connected to the output shaft of the hermetically sealed gear box meshes with the first gear 90 and can operate in an unsealed environment. Thus, the first drive system rotates the yoke 84 in a clockwise or counterclockwise direction to 360 degrees (or a larger angle). In use, the armature assembly 80 may be covered with a weatherproof cover (not shown), thereby protecting the drive system from ice, rain, sand, and the like.

  The mandrel 88 is attached through a through hole 87 provided in the vicinity of the ends of the two arms 86. Although not shown, an appropriate bearing or bushing may be provided in this case as well. Each end of the mandrel 88 ends with a plate 89 that is used for attachment to the back side of the solar panel as shown in later figures. The exact form of the plate 89 depends on the attachment means used in attaching the solar panel to the armature assembly 80. Here, a groove is provided on the outer periphery of the plate 89, whereby the fastener is received and the armature assembly 80 is connected to the solar panel. The yoke 84 and the mandrel 88 are provided with a second drive system that controls the inclination angle of the solar light tracking unit 200. A first gear 95 is attached to the mandrel 88, and a second gear 96 that meshes with the first gear 95 is attached to the yoke 84. In the present embodiment, the first gear 95 is not a perfect circle like the first gear 90 but a fan-shaped gear. Since yawing in a wider range (ie, an angle exceeding 180 degrees) can be performed by the first drive assembly including the gears 90 and 91, the inclination angle of the solar tracking unit 200 is 90 degrees. It is considered sufficient to adjust in the range of. In another example, the shape of the gear 95 may be a semicircular shape instead of a quadrant. That is, depending on how close the solar panel is to the mandrel 88, a complete circular gear may not be provided on the mandrel 88. The second gear 96 is controlled by a further drive system that includes a motor and gear box 97. Here, the drive system is attached to the yoke 84. As an example, a suitable drive assembly has a weathering and durability stepper motor. This stepping motor has an output shaft, and the output shaft is connected to a closed gear box having an output shaft with a pinion gear (second gear 96). Therefore, the pinion gear (second gear 96) can supply higher torque than the stepping motor, and the increase in torque depends on the gear ratio of the gear included in the hermetic gear box. The pinion gear connected to the output shaft of the hermetically sealed gear box meshes with the first gear 95 and can operate in an unsealed environment. In the embodiment of FIG. 8, the motor 97 and the second gear 96 are attached to the arm 86 closest to the gear 95.

  Although a spur gear is shown in FIG. 8, other types of gears are employed to provide movement in two planes that are also perpendicular to the shaft 82 and mandrel 88 and substantially perpendicular to each other. May be. Although not shown in the drawing, a tension spring may be provided to ensure engagement between the teeth of the gears 91 and 96 and the teeth of the gears 90 and 95. Although not shown, a home switch may be provided on each of the two drive assemblies and used to return the solar panel to the default position. Both motors 92 and 97 can be controlled using a local control unit described later.

  Various suitable shapes can be employed for the solar panels attached to the armature assembly 80. For example, the solar panel includes one or more flat plate solar panel modules formed from semiconductors such as silicon, gallium arsenide, cadmium telluride, and copper indium gallium arsenide. Alternatively, the solar panel may be a concentrating solar panel that employs a condensing optical system. In the case of a concentrating solar panel, the solar panel includes individual optical modules with PV cells. The optical module may or may not include an integrated electronic device such as a power efficiency optimizer. The optical system provided in each optical module may include an optical system composed of a plurality of components. Embodiments of assemblies comprising multiple optical systems are disclosed in US Patent Application Publication No. 2011/0011449 filed on February 12, 2010 and US Patent Application Publication No. 2008/0271776 filed on May 1, 2008. In the issue. An integrated concentrating PV module is described in US Patent Application Publication No. 2011/0273020 filed April 1, 2011. The entire contents of the applications mentioned herein are hereby incorporated by reference. Individual optical modules may be connected in series to a column of optical modules, and can be sequentially connected in parallel to other columns to form an array of optical modules. A solar panel module may be formed by arranging one or more rows of optical modules in one plane.

  FIG. 9 shows the first solar panel 210 in the “podium” shape. Here, the solar panel module which consists of an optical module is arrange | positioned by the structure which mutually shifted | deviated, and has become a two-stage panel. A solar panel module is formed by attaching a row of optical modules to one or more crosspieces 212. The cross piece 212 can be made of aluminum or a material suitable for providing the weather resistance, stiffness, and stability required for field use. The cross piece 212 is provided with at least one lower step 213 and at least one upper step 214, each supporting a plurality of optical modules 218. Although the cross piece 212 in FIG. 9 includes one upper step 214 between two lower steps 213, a plurality of upper steps 214 may be alternately arranged between the plurality of lower steps. . In this embodiment, the optical module 218 is attached to a heat sink 216 that separates the optical module 218 from the cross piece 212. The heat sink can be made from a suitable material. In FIG. 9, the heat sink 216 is manufactured from extruded aluminum and has an “I-shaped” beam shape including a support portion 216a. Here, the support portion 216a is attached to the cross piece 212 so that the optical module 218 is substantially parallel to the step portions 213 and 214, and the pair of optical modules on the step portions 213 and 214 are aligned in substantially the same plane. It is attached. A series of fins 216b are provided to dissipate heat. The plurality of crosspieces 212 to which the rows of optical modules are fixed are themselves connected by a beam 215 shown in FIGS. An armature assembly 80 can be attached to the beam 215.

  Another solar panel 220 having a “delta” shape is shown in FIG. In the present embodiment, the crosspiece 222 includes two arms 224 that are connected at an angle at the central apex. Also in this case, the optical module 230 is attached to the heat sink 228, and the heat sink 228 is sequentially attached to the arm 224 by the support portion 228a. As described above with respect to FIG. 9, different shapes may be employed for the heat sink. However, the modified “I-shaped” beam shape shown in FIG. 10 allows the individual optical modules 230 to be mounted parallel to each other in a step-like arrangement. Although not shown in FIG. 10, the armature assembly 80 can be attached to the beam again. Thus, both of these offset shapes 210 and delta shapes 220 shift adjacent optical module rows to different height positions, resulting in improved air flow around the solar panel. Yes. Therefore, the load due to wind is reduced and the movement of heat from the heat sink is promoted, and the solar panels 210 and 220 can be operated with higher efficiency than in other cases. Similarly, a solar panel including a plurality of flat plate-like solar panel modules may have a shape shifted from each other or a delta shape. In some embodiments, the solar panel module is directly attached to at least one lower 213 and at least one upper 214 or angled arm 224 without using heat sinks 216,228. May be.

  FIG. 11 shows the connection between the cross piece 212 and the beam 215 described above. The plate 89 provided on the mandrel 88 of the armature assembly 80 may be secured to the beam 215 using suitable securing means. Individual solar tracking units 200 and panels are effectively mounted with their center of gravity aligned with the position of the leg assembly 30. Thereby, the stability of the whole sunlight tracking unit 200 improves. The offset shapes and delta shapes of solar panels 210 and 220 also improve stability once installed. That is, when the solar panel is attached to the armature assembly 80, the axis of rotation (rotation that defines the tilt angle by the mandrel 88) due to the shifted arrangement of adjacent optical modules is the panel 210, It is aligned with the center of gravity of 220 in a substantially straight line. This is illustrated in FIGS. 9 and 10 by the position of the mandrel 88 relative to the solar panels 210, 220. The panel design thus reduces the total energy required to drive the panel between different orientations and helps maintain tracking accuracy.

  Alternatively, the solar panel is “planar” sunlight in which all light receiving parts are provided on one surface, whether it is a flat plate or a concentrating optical device. It may have a panel shape (not shown). If the center of gravity of the solar panel and the panel frame for attaching the solar panel to the armature assembly is not centered on the mandrel 88, the center of gravity moves vertically against gravity when the mandrel 88 rotates. As a result, the system will have to work accordingly. Therefore, it is more convenient to maintain the center of gravity of the solar panel and the panel frame at the center of the mandrel 88. In order to maintain the center of gravity of the solar panel and the panel frame in the center of the mandrel 88, a counterweight may be attached to the solar panel or panel frame so that the center of gravity can be shifted to a desired position (not shown). .

  FIG. 11 shows what can be a conduction path for grounding the structure supporting the solar light tracking unit 200. The first end of the conductor 1100 is fixed to the beam 215 with a fastener 1101. The conductor 1100 extends toward the fastener 1103 and is secured to the gusset 83 with the fastener 1103. The second end of the conductor 1100 is fixed at the attachment end 35 of the leg assembly 30, for example, at a fastener 1105 that joins the leg assembly 30 and the armature assembly 80. The conductor 1100 is secured to the armature assembly 80 leaving sufficient slack allowed for operation of the solar tracking unit 200 using a drive assembly for yawing and tilting. As the conductor 1100, an appropriate ground wire or ground cable such as an insulated wire equivalent to 10 gauge can be used. The fasteners are of any type, if appropriate, but preferably use self-tapping screws that are corrosion resistant and are painted to provide resistance to the field environment. Can do.

  FIG. 12 shows another wiring for grounding the structure that supports the solar light tracking unit 200. In this example, the first length portion of the conductor 1201 is fixed between the fastener 1101 and the fastener 1102 provided on the arm 86 of the yoke. A second length of conductor 1202 is attached to gusset 83 with fasteners 1103 and attached to leg assembly 30 with fasteners 1105. That is, rather than extending the cable to form a conductive path, the yoke 84 and gusset 83 become part of the conductive ground path. Thereby, compared with the wiring of FIG. 11, the twist amount and / or the bending amount of the cable can be further reduced. This is because when the solar tracking unit 200 moves along a plurality of axes by the drive assembly for yawing and tilting, the movement of the conductors 1201 and 1202 is reduced.

  Each of the box-shaped frames 10 deployed on the site is preferably arranged so that one truss extends in the north-south direction. FIG. 13 shows an example of the arrangement and posture of the frame 10. In this example, three box-shaped frames 10 are arranged on the site such that the shorter truss extends in the north-south direction. In order to maintain the spacing between the frames 10, spacing arms 1302, 1304 of a predetermined length are attached to each truss or leg assembly of the frames 10 adjacent to each other. The spacing arms 1302 and 1304 may be arranged so as to be aligned with the upper cord members 14 and 24, or may be arranged along the ground. For example, as shown in FIG. 13, the spacing arm 1302 extending in the north-south direction can be arranged in line with the upper cord members 14 and 24. On the other hand, the spacing arm 1304 extending in the east-west direction can be located at or near the ground surface. Such an arrangement makes it easy for a person to pass between the frames 10 and allows the vehicle to run between the frames 10 arranged in the east-west direction when there is enough space. Become. The interconnection of the frame 10 as described above makes the overall structure of the frame 10 stronger, so that it is not necessary to add ballast to the frame 10 from the outside. The lengths of the spacing arms 1302 and 1304 and the dimensions of the frame 10 are selected according to a desired interval between the individual solar tracking units 200. Solar panel size and / or environmental conditions such as shade and wind speed, as well as related components, transportation and land use costs, optimal power generation, as at least some of the factors to consider in setting this interval Production conditions based on analysis such as quantity are listed. When using the panel as shown in FIG. 11 or 12, for example, the distance between the leg assemblies arranged in the north-south direction may be about 3.44 m, and the distance between the leg assemblies arranged in the east-west direction is about 4.98 m. Also good.

  In addition to the physical interconnection between the solar tracking assemblies 100 for the purpose of improving stability, the individual solar tracking units 200 may be interconnected within the single solar tracking assembly 100 as well. Good. Each assembly 100 may be provided with a local control unit (LCU) 1402 as shown in FIG. One solar control unit 200 on one frame 10 is controlled by one LCU 1402. Alternatively, the solar tracking unit 200 on the plurality of frames 10 may be controlled by one LCU 1402 (not shown). For example, a single cluster composed of a plurality of frames 10 is formed by positioning and arranging a plurality of frames 10 so that an LCU 1402 is attached to only one frame 10 and not attached to another frame 10. Can do. In the case of such a cluster, a wire can be run from one LCU 1402 to each of the solar light tracking units 200 on the frame 10. When the frame 10 has four solar tracking units 200, two solar tracking units 200 are connected in series with each other, and two pairs of the obtained solar tracking units 200 are connected in parallel with each other, High voltages are possible and power losses in the interconnected wires can be reduced. Each pair of solar tracking units 200 can include a current sensor and / or a voltage sensor (not shown) that interact with the LCU 1402. In some examples, the solar tracking units 200 on one frame are individually controlled, and each can include a current sensor and / or a voltage sensor.

  The LCU 1402 receives input data such as astronomical data (programmed in the LCU 1402 or obtained through a network), numerical values of current sensors or power sensors, numerical values of solar position sensors on each solar tracking unit 200, and the like. Can be received. The LCU uses these data to locate the solar panel of each solar tracking unit 200, output signals to control the motor, and communicate with other components on-site or on the network Output a signal. The LCU 1402 may be provided with a temperature sensor that measures the ambient temperature where the assembly 100 is installed. If an ambient temperature exceeding a predetermined threshold temperature is detected, the LCU 1402 can stop tracking the sun until the ambient temperature returns to an operable temperature (eg, -20 ° C to + 50 ° C). In addition, when the wind speed exceeds a predetermined threshold (for example, a numerical value exceeding 35 mph), the LCU 1402 sends a signal to the motors 92 and 97 to bring the solar tracking unit 200 into a horizontal “stowed” posture. Can be output. If the individual assembly 100 does not include a temperature sensor (or wind speed sensor), deliver weather data to the LCU 1402 from the center of the solar farm where the assembly 100 is installed, or from another network source through a communication line. Can do.

  The LCU 1402 can calibrate the sun position predicted based on the received astronomical data. That is, the LCU 1402 compares feedback from the solar sensors and power sensors (that is, current sensors and / or voltage sensors) of each solar tracking unit 200 according to the iterative process shown in FIG. Perform calibration. In this process, the LCU 1402 calculates the initial position of the sun at 1510, receives feedback from the sun sensor at 1520, and calculates the deviation between the data received from the sun sensor and the calculated sun position at 1530. To do. At 1540, the difference in orientation between the feedback position and the calculated position is obtained. At 1550, coordinate conversion is performed on the calculated position based on the difference obtained at 1540. While the LCU 1402 continues to receive feedback from the sensor at 1520, further adjustments to the conversion are possible. Such a transformation also applies to other sun positions calculated by the LCU 1402. Thereby, the positions of the solar panels 210 and 220 on the individual solar tracking units 200 are controlled. As described above, the sun sensor on each sunlight tracking unit 200 is useful for compensating for inconveniences such as terrain undulation and incomplete installation. However, if the position of the solar sensor is shifted with respect to the individual solar panels 210 and 220, the performance may continue to deteriorate. In view of this, the LCU 1402 additionally or alternatively tracks the mechanical maximum output point (MPP) of each panel or panels using current and / or voltage sensors and optimizes each panel's optimal output. To determine the alignment position, the panel can be calibrated by gradually adjusting the alignment along the panel axis.

  In the field, as shown in FIG. 14, a plurality of LCUs 1402 can be connected to each other by field wires. Field wire 1400 may include a power bus for assembly 100 and a communication line for each LCU 1402. One example is the introduction of power line communication that allows communication between a wide area control unit or monitoring unit (not shown) and the LCU 1402. The wide area control unit receives data from a plurality of LCUs 1402 in the farm or sub-farm configured with the assembly 100. The wide-area control unit can receive data such as solar sensor data, each pair of solar light tracking units 200, or the power or current values of the entire assembly 100, and can also provide instructions for motor control, astronomical data, etc. Data necessary for operation can be transmitted to the LCU 1402. This wide area control unit can also control individual solar light tracking units 200, and in this case, the wide area control unit has priority over the corresponding LCU 1402. For example, the solar tracking unit 200 can be forced into a stowed posture or a posture capable of maintenance and repair by the operation of the maintenance person using the wide-area control unit. Each operation can be stopped. In some examples, wireless (RF) communication or wired serial communication may be introduced between the LCU 1402 and the wide area control unit. Also, in order to allow remote operation of the wide area control unit and individual LCUs 1402, a person may optionally access and operate the wide area control unit through a public or private network such as the Internet. Thereby, the network of the solar light tracking unit 200 which can each operate | move independently is completed. A central control system may be used to control each solar light tracking unit 200.

  For some or all of the LCUs 1402, wiring by field wires can be made unnecessary. In order to achieve this, wireless communication (for example, by radio frequency) is introduced between the LCU 1402 and the wide area control unit, and the LCU 1402 is supplied with power generated by the solar panel to be tracked. Alternatively, the LCU 1402 is supplied with power generated by one or more auxiliary solar panels connected directly thereto. The auxiliary solar panel does not contribute to the main power bus that conducts the power generated by the solar tracking unit 200 in the solar farm. Further, the auxiliary solar panel can be integrated with a case (not shown) of the LCU 1402.

  The wide area control unit or monitoring unit can be integrated with one of the LCUs 1402 in the solar farm. In the case of a small-scale solar farm, one LCU may be sufficient. In this case, one LCU functions as an LCU and a wide area control unit at the same time as controlling a plurality of tracking devices.

  FIG. 16 shows an example layout of an array 1600 of solar subfarms or assemblies comprised of the solar tracking assemblies 100a-100i described herein. The array 1600 in FIG. 16 is composed of nine assemblies 100 arranged in a grid. The assembly 100 is connected in its rows by spacing arms 1602, 1604 and field wires. These spacing arms 1602 and 1604 also serve as a path between the assemblies 100. It can be seen that the assemblies 100e and 100f do not include all the components of the solar tracking unit 200.

  During installation of the assembly 100, the structure that supports each solar tracking unit 200 is typically grounded by the conduction path described above in connection with FIGS. In order to prevent unnecessary voltage from being accumulated in the structure (crosspiece, beam, armature assembly, etc.) that supports the frame 10 and the solar tracking unit 200, ground electrodes such as ground bars and ground spikes are connected to each leg assembly 30. can do. Further, the spacing arms 1602 and 1604 serve as a conduction path between the solar light tracking units 200. Thus, to reduce installation costs, the primary ground location of a ground rod or ground spike 1650 connected to one of the frames 10 in the array 1600 is the solar farthest from the ground spike 1650 and the spike. The route to the light tracking unit 200 is selected to be the shortest.

  According to the frame 10 and the solar light tracking unit 200, the solar light tracking assembly 100 can be easily installed on the site. As described above, terrain relief can be compensated by various characteristics of the assembly 100. This is advantageous for roughing the site to roughen the ground and ensure access during maintenance. In places where the ground and soil are not stable, crushed concrete aggregates may be sown to assist in stabilizing the ground and / or preventing the growth of weeds and the like. The pre-wired frame 10 has three trusses 12 and 22 and is in a folded state. The frame 10 is unfolded and the fourth trusses 12 and 22 are fixed at specified positions. In addition, the foot member 37 of each leg assembly 30 is adjusted as necessary to compensate for the undulation of the terrain. However, this adjustment may not be completely accurate. This is because various changes in the terrain can be compensated by the automatic calibration function of the tracking module. Next, an armature assembly 80 is assigned to each leg assembly 30 and is inserted into the mounting end 35 of the leg assembly 30 and secured with a fastener. Next, the solar panels 210 and 220 are fixed to the armature assembly 80 via the plates 89 and fasteners. The overall height of the frame 10 and the armature assembly 80 is a height that does not require cranes or similar equipment to install the solar panels 210 and 220. In another embodiment, solar panels 210, 220 are shipped with removable handles. This allows the person in charge to lift the solar panels 210 and 220 and place them on the armature assembly 80 during installation.

  A ground wire is then attached as needed. In addition, motors 92 and 97 are connected to wires in the range of the frame 10, and these wires are guided to the local control unit 1402. The wires connected to the motors 92, 97 may partially pass through the leg assembly 30 and / or the truss assembly. The local control unit 1402 is attached to the frame 10 and connected to a wire already provided in the frame 10. Next, the local control unit 1402 is connected to the power bus connecting the other assemblies 100 to each other. For wiring with field wires, pre-cut and terminated PV-rated cables are used, which include a PV power bus and a local control unit power / communication bus. The wiring by the field wire may be laid directly on the ground between the solar tracking assemblies 100. However, if it interferes with the maintenance path between assemblies, the cable should be buried in the ground or otherwise protected.

  When an air hose or a water hose is provided in the frame 10, the hose is connected to its source. The hose is connected to a cleaning tool (such as a spray gun) and used to clean the solar tracking module 200 and other components of the assembly 100.

  Although various embodiments of the present invention have been described in detail by way of examples, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit of the present invention. The present invention includes all such variations and modifications without departing from the scope of the appended claims.

Claims (24)

A frame for mounting a plurality of solar tracking units,
A plurality of leg assemblies that are connected to each other by a plurality of trusses to form a stable and stable structure by the weight of the frame itself;
Each of the leg assemblies includes a shaft having a shaft with a mounting end to which one of the plurality of solar tracking units is mounted on the ground.   At least some of the plurality of trusses are hinged to the plurality of leg assemblies so that the frame has a stable structure in the installed state and is folded substantially flat in the folded state. The frame of claim 1, wherein:   Each of the leg assemblies further comprises an adjustable foot member that engages the ground, the foot member being attached to the end of the shaft opposite the mounting end. The described frame.   The frame of claim 3, wherein the adjustable foot member comprises a plate member extending from a stem detachable from the shaft of the leg assembly.   Each of the trusses includes an upper cord member, a lower cord member, and a plurality of truss members mounted therebetween, the truss member supporting and stabilizing the upper and lower cord members. The frame according to any one of claims 1 to 4, wherein The leg assembly further comprises at least a first flange unit and a second flange unit;
Each of these flange units includes a plurality of flanges extending radially from positions in the length direction of the shaft,
The first flange unit is arranged at a position aligned with the lower cord member belonging to at least one of the trusses,
The second flange unit is spaced apart from the first flange unit and aligned with the upper cord member belonging to at least one of the trusses,
Each of the flanges is a frame comprising at least one through hole extending therethrough;
A plurality of fasteners for hinged connection of the truss to the leg assembly;
6. The frame of claim 5, wherein each of the fasteners connects the upper or lower cord member belonging to one of the trusses to an associated flange through a through hole provided in the flange.   The frame according to claim 5 or 6, further comprising at least one of a cable, a wire, and a hose pre-threaded through at least one of an upper cord member and a lower cord member belonging to at least one of the trusses. . Further comprising at least one spacing arm having a predetermined length;
Each of the spacing arms is connected to one of the leg assemblies at a first end, and the second end of the spacing arm is used for connection with a leg assembly belonging to an adjacent frame. The frame according to any one of 7. A first leg assembly, a second leg assembly, a third leg assembly, and a fourth leg assembly;
A first truss, a second truss, a third truss, and a fourth truss;
The first leg assembly is hinged to a first end of the first truss;
The second leg assembly is hinged to a second end of the first truss and a first end of the second truss;
The third leg assembly is hinged to a second end of the second truss and a first end of the third truss;
The fourth leg assembly is a frame hinged to a second end of the third truss;
In the installed state, a first end of the fourth truss is connected to the fourth leg assembly and a second end of the fourth truss is connected to the first leg assembly, thereby The frame according to any one of claims 1 to 8, wherein a stable structure is formed. With an array of solar tracking assemblies in electrical communication with each other,
Each of the solar tracking assemblies includes a frame that supports a plurality of solar tracking units,
Each of the solar tracking units comprises an armature assembly capable of moving a solar panel about a plurality of axes,
A system wherein a corresponding local control unit communicates with at least one of the plurality of solar tracking units to control the armature assemblies belonging to each of them. A wide area control unit for communicating with each local control unit belonging to the array of solar tracking assemblies;
The system according to claim 10, wherein the wide-area control unit is capable of issuing commands to control individual local control units and the plurality of solar light tracking units that communicate with the local control units.   The system according to claim 10 or 11, wherein the local control unit performs communication with each of the plurality of solar light tracking units in order to control the armature assemblies belonging to each of them.   The system according to claim 10 or 11, wherein each of the solar light tracking units can be operated independently by the corresponding local control unit.   12. The system according to claim 10 or 11, wherein the local control unit is capable of controlling the plurality of solar tracking units with respect to other solar tracking assemblies belonging to the array.   15. The frame of any one of claims 10 to 14, wherein the frames belonging to adjacent solar tracking assemblies are connected to each other and spaced from each other by at least one spacing arm having a predetermined length. System. The structure supporting each solar light tracking unit is electrically grounded via the frame to which the solar light tracking unit is attached,
The system of claim 15, wherein the frames belonging to the array of solar tracking assemblies share a common ground electrode via the spacing arm.   The system according to any one of claims 10 to 16, wherein wiring for interconnecting the plurality of solar light tracking units with a local control unit corresponding to the plurality of solar light tracking units is provided in the frame.   18. The frame of any one of claims 10 to 17, wherein the frame comprises a plurality of trusses hinged to a plurality of leg assemblies, each of the armature assemblies being attached to one of the corresponding leg assemblies. The system described in one. In each of the solar tracking assemblies, each of the armature assemblies includes a yoke that is rotatable about a first axis;
The yoke supports a mandrel rotatable about a second axis;
The solar panel includes a plurality of solar panel modules, and the solar panel modules are attached so that they are in a mutually offset relationship and the mandrel is aligned substantially in line with the center of gravity of the solar panel. The system according to any one of claims 10 to 18.   20. The system according to claim 10, wherein each of the sunlight tracking units includes a sunlight sensor that determines a direction of sunlight that is normally incident. At least one of the solar tracking assemblies comprises four solar tracking units;
The solar light tracking unit is connected so that the two pairs are connected in series, and the two pairs are connected in parallel.
21. A system according to any one of claims 10 to 20, wherein the solar tracking assembly is provided with a current sensor used for each pair of solar tracking units.   The local control unit receives current sensor data from each of the current sensors and controls the operation of the armature assembly based on at least one of the received current sensor data and solar position data. The described system.   The system according to claim 22, wherein the local control unit receives solar position data from a sunlight sensor provided in each of the sunlight tracking units. The local control unit has a configuration suitable for calibrating solar position data calculated from astronomy data obtained in advance,
24. In calibration, a deviation between some received position data and the calculated solar position data is determined, and the deviation is applied as a transformation to the calculated solar position data. The described system.

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